Assessment of the waste water effect on The Presence and the density of the Tigris River benthic fauna by using biodiversity index in AL-Kut City.

Abstract

The present study aimed to investigate the effect of heavy water (sewage water) on the quality of water and the living organisms in the water, especially the benthic invertebrates. Five stations were selected in the river at AL-Kut city, the first is before sewage pipe , the second near the sewage pipe and third , fourth and fifth were after the position of sewage pipe. The samples were collected monthly during the period from July- December 2015. The study includes several statistical indexes (Relative abundance index, Constancy Index, Shannon-Weiner Diversity Index, Species Uniformity Index and Species Richness Index). The results revealed that there were decreasing in the studies indexes, at station (2) which is near the position of the sewage pipe. The benthic invertebrates biodiversity was also affected by the sewage pipe at the station (2). Results of the present study recorded the highest percentage and it was 45.1% Oligochaeta , Chironomidae was 29%, Mollusca was 19.4% and Nematode was 6.5%.